Why Black Women Lose Less Weight On Same Diet and Fitness Plan As White Women

It may be harder for black women to lose weight. A new study published in the International Journal of Obesity showed that "African-American women may need to eat fewer calories or burn more than their Caucasian counterparts to lose a comparable amount of weight." When following the same same diet and exercise guidelines for six weeks, obese Caucasian women lost an average of seven pounds more than African American counterparts. And the reason seems to hinge on slower resting metabolism, which leads to burning less calories naturally throughout the day.

Previous studies have found similar weight loss discrepancies and suggested that diet and exercise interventions weren't "culturally sensitive," said lead investigator James P. DeLany, a professor at the University of Pittsburgh School of Medicine. "But even in research projects that were designed to address those possibilities, the difference in weight loss remained." So DeLany and colleagues decided to look at potential metabolic reasons for the difference.

The team measured weight changes, energy expenditure, physical activity, and caloric intake among 39 African-American and 66 Caucasian women during a six-week period. All were obese based on body mass index. At the end of the study, the African American women had lost about seven pounds fewer on average though their starting BMI, diets, and exercise levels had been similar. However, the African American women had lower resting metabolic rates and thus expended less energy throughout the day, researchers found.

"We prescribe how many calories are allowed and how much activity is needed during weight loss interventions based on the premise that people of the same weight have similar metabolic rates," said DeLany in a statement. "But to account for their lower metabolic rate, African-American women must further reduce the number of calories they eat or use up more of them with exercise in order to lose the same number of pounds in the same time span as a Caucasian woman of the same weight."